Huge explosion and fire rip through Essex industrial site

Watch: Moment of explosion as huge fire breaks out at Essex industrial site

A huge explosion triggered by a fire spreading to a store of fertiliser tore through an industrial unit in Essex on Friday, with more than 100 firefighters sent to tackle a massive fire and a "major incident" declared.

Footage which captured the moment of the explosion showed a ball of flames erupting into the air and people fleeing, while witnesses told BBC News the sound was "like a bomb" and as loud as a "sonic boom".

A number of buildings and vehicles on farmland were gutted by the fire, which was expected to keep burning into Saturday.

People living near the fire - which happened close to the village of Rettendon, south of Chelmsford - were urged to keep their windows closed as smoke spread.

As of Friday evening it was not clear whether there had been casualties.

In an update on Friday evening, Dave Bond of Essex County Fire and Rescue Service said: "While on the scene, fertiliser inside one of the units exploded and residents across the county have reported hearing and feeling it.

"This is why we declared a major incident and I want to reassure our residents that there is no wider risk to the public at this time."

He said "everybody at the scene is safe" but that residents have been evacuated.

East of England Ambulance Service said its hazardous area response team and the police were also in attendance.

Earlier on Friday evening, Bond said there was still "significant smoke" at the scene but he believed that the fire had been "surrounded".

Sam Dimond, owner of event production company Spotlight Sound, said he had lost his livelihood in the fire. The headquarters of his business was based on the industrial site.

He said: "It's gone, basically. Lots and lots of people have lost their livelihoods. We've got customers to serve, we've got employees that have a job, and at the minute they don't have a place of work to go back to."

Adrian Walker, 46, from Ashingdon, said: "The ground shook, buildings shook, windows rattled, birds flew off - and I am 15 miles away.

"I've never heard anything like it. At first, I thought it was the MoD in Shoeburyness trying out some new ordnance, but it was heard and felt for miles around."

Matthew Fergusson, from Wickford, described a "massive explosion" that sent a "mushroom cloud" towering into the sky.

"I thought someone had dropped something heavy upstairs, but when I went outside the whole street was out," he added.

Steven Whan, 58, from Bicknacre, near Danbury, thought he had heard a jet's sonic boom when the explosion occur